Genetic defects in bone morphogenetic protein type II receptor (BMPRII) signalling and inflammation contribute to the pathogenesis of pulmonary arterial hypertension (PAH). The receptor is activated by bone morphogenetic protein (BMP) ligands, which also enhance transcription. A small-molecule BMP upregulator with selectivity on vascular endothelium would be a desirable therapeutic intervention for PAH.We assayed compounds identified in the screening of BMP2 upregulators for their ability to increase the expression of inhibitor of DNA binding 1 (Id1), using a dual reporter driven specifically in human embryonic stem cell-derived endothelial cells. These assays identified a novel piperidine, BMP upregulator 1 (BUR1), that increased endothelial Id1 expression with a half-maximal effective concentration of 0.098 μmol·L Microarray analyses and immunoblotting showed that BUR1 induced BMP2 and prostaglandin-endoperoxide synthase 2 (PTGS2) expression. BUR1 effectively rescued deficient angiogenesis in autologous endothelial cells generated by CRISPR/Cas9 and patient cells.BUR1 prevented and reversed PAH in monocrotaline rats, and restored BMPRII downstream signalling and modulated the arachidonic acid pathway in the pulmonary arterial endothelium in the Sugen 5416/hypoxia PAH mouse model.In conclusion, using stem cell technology we have provided a novel small-molecule compound which regulates BMP2 and PTGS2 levels that might be useful for the treatment of PAH.

Murine MS‐K and NFSA cell lines formed tumor after inoculation into mouse and both cell lines expressed high level of vascular endothelial growth factor‐A (vegf‐A) and produced same level of VEGF‐A. However, poor blood vessel formation, and necrosis was significantly observed in NFSA‐tumor, contrary to well‐developed blood vessel formation in MS‐K tumor. The microarray analysis showed high expression of fibroblast growth factor‐10 (fgf‐10) in MS‐K than NFSA. In this report, the role of fgf‐10 on tumor growth was studied. MS‐K enhanced more proliferation of endothelial cells by direct co‐culture than NFSA, and rFGF10 supported the proliferation of HUVEC in combination with VEGF‐A. fgf‐10‐knocked down MS‐K, MS‐K (fgf‐10‐KD), proliferated slower in vitro and the tumorigenicity of them was also slower than control. The blood vessel formation in these MS‐K (fgf‐10‐KD) clones was reduced compared with the MS‐K (normal). qPCR analysis showed the suppression of vegf‐A, vegf‐C and fgfr‐1‐expression in the MS‐K (fgf‐10‐KD) clones. Taken together, these results indicated that FGF10, which was produced from tumor cells, was essential for the proliferation of tumor cell itself and also supports proliferation of endothelial cells. Thus, FGF10 plays an important role for tumor growth by both paracrine and autocrine manner.

We previously showed that interleukin (IL)-18 produced by NFSA cells induced the M1 type of macrophages in NFSA tumors, caused the destruction of endothelial cells in vitro and may have resulted in the necrosis of NFSA tumors by enhancing macrophage phagocytosis and cytotoxicity. However, the effect of IL-18 on blood vessel formation in vivo has not been elucidated. MS-K cells do not express il-18, and they form tumors with well-developed blood vessels. Here, we established IL-18-over-expressing MS-K cell clones (MS-K-IL-18) to address the roles of IL-18 in angiogenesis. The over-expression of IL-18 inhibited the proliferation rate of the MS-K-IL-18 cells in vitro and blood vessel formation in the MS-K-IL-18 tumors. Interestingly, CD14-positive cells from the MS-K-IL-18 tumor had up-regulated expression of the M1-type macrophage marker il-6 and down-regulated expression of interferon (ifn)-c. Furthermore, FACS analysis showed more accumulation of CD11b+/CD80+ M1 macrophages in the MS-K-IL-18 tumors than in the parental MS-K tumor. Moreover, an in vitro coculture assay showed that MS-K-IL-18-conditioned medium (CM) stimulated macrophages to induce the apoptosis of endothelial cells. Cumulatively, our data showed that IL-18 inhibited tumor blood vessel formation in vivo.

a b s t r a c tMicroRNAs (miRNAs) are small non-coding RNAs that participate in a large variety of biological processes. In this paper, the spatiotemporal expression pattern of miR-370 was characterized during mouse embryonic development, and was found to be stage-and tissue-specifically expressed. In addition, through luciferase reporter assays and western blot analyses, DNA methyltransferase 3A (Dnmt3a) was identified as a directly regulated target of miR-370. Altogether, our results indicate that miR-370 may play important roles in the morphogenesis of diverse organs, especially brain and adrenal glands, by mediating Dnmt3a expression during mouse development.

We previously demonstrated that IL-18 and CCL11 were highly expressed in an NFSA tumor cell line that showed limited angiogenesis and severe necrosis. However, IL-18 was not responsible for the immune cell accumulation and necrosis. Here, we attempted to clarify the relevance of CCL11 in angiogenesis and tumor formation. We established CCL11-overexpressing MS-K cell clones (MS-K-CCL11) to assess the role of CCL11 in immune cell accumulation and angiogenesis. The MS-K-CCL11 cells did not form tumors in mice. MS-K-CCL11-conditioned medium (CM) and recombinant CCL11 induced macrophage and eosinophil differentiation from bone marrow cells. The MS-K-CCL11-CM effectively recruited the differentiated eosinophils. Furthermore, the eosinophils damaged the MS-K, NFSA and endothelial cells in a dose-dependent manner. Administration of an antagonist of CCR3, a CCL11 receptor, to NFSA tumor-bearing mice restored the blood vessel formation and blocked the eosinophil infiltration into the NFSA tumors. Furthermore, other CCL11-overexpressing LM8 clones were established, and their tumor formation ability was reduced compared to the parental LM8 cells, accompanied by increased eosinophil infiltration, blockade of angiogenesis and necrosis. These results indicate that CCL11 was responsible for the limited angiogenesis and necrosis by inducing and attracting eosinophils in the tumors.